West of Western Sahara, Mauritania and Senegal, off the coast of West Africa, is an atmospheric phenomenon known as Kármán Vortex Streets. These parallel rows of oppositely spinning vortices, caused by the unsteady separation of flow of a fluid around blunt bodies, can be seen trailing off the Canary Islands (above) and off the Cape Verde islands (below). Some dust can also be seen spreading off the coast of Mauritania.